I was wondering if anyone has tested this or has any information on this. In specifically Canon printers, will it cost more to operate a 7 ink cartridge printer than a 5? One way I can think of it is that buying 7 cartridges is going to cost more than 5. But then the other way I can think of it is that it is all going to even out in the end because using those two extra cartridges is going to use less ink from the others. So which way is true? Will then end up costing the same to run or will the 7 be more costly?